Over four games and four years the 'Sorcery!' series has evolved from linear gamebook adaptations to fully open-world story-games. Players explore freely, encountering narrative content in any order and creating hundreds of small and large scale consequences, all of which are persistent. With the game rendered entirely through prose text, continuity is critical to ensuring believability, and in this talk Jon will outline how inkle Ltd designed and scripted the game to work in an ad-hoc fashion, using defensive logic to ensure the story gets told and makes sense regardless of how it comes about. He'll illustrate with concrete examples from Sorcery!'s later parts, '80 Days', and their upcoming title, and discuss some of the resulting challenges.